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arXiv · 2106.02591

Cross-correlating Astrophysical and Cosmological Gravitational Wave Backgrounds with the Cosmic Microwave Background

Angelo Ricciardone·Lorenzo Valbusa Dall'Armi·Nicola Bartolo·Daniele Bertacca·Michele Liguori·Sabino Matarrese
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Abstract

General Relativity provides us with an extremely powerful tool to extract at the same time astrophysical and cosmological information from the Stochastic Gravitational Wave Backgrounds (SGWBs): the cross-correlation with other cosmological tracers, since their anisotropies share a common origin and the same perturbed geodesics. In this letter we explore the cross-correlation of the cosmological and astrophysical SGWBs with Cosmic Microwave Background (CMB) anisotropies, showing that future GW detectors, such as LISA or BBO, have the ability to measure such cross-correlation signals. We also present, as a new tool in this context, constrained realization maps of the SGWBs extracted from the high-resolution CMB {\it Planck} maps. This technique allows, in the low-noise regime, to faithfully reconstruct the expected SGWB map by starting from CMB measurements.

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Angelo Ricciardone, Lorenzo Valbusa Dall'Armi, Nicola Bartolo, Daniele Bertacca, Michele Liguori, Sabino Matarrese. 2021-12-30. Cross-correlating Astrophysical and Cosmological Gravitational Wave Backgrounds with the Cosmic Microwave Background. https://doi.org/10.1103/physrevlett.127.271301

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